Light emitting device and manufacturing method for same

ABSTRACT

Disclosed are a light emitting device and a method of manufacturing the same. The light emitting device includes a support substrate, a reflective ohmic contact layer on the support substrate, a functional complex layer including a process assisting region and ohmic contact regions divided by the process assisting region on the reflective ohmic contact layer, and a light emitting semiconductor layer including a second conductive semiconductor layer, an active layer, and a first conductive semiconductor layer on each ohmic contact regio.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of co-pending U.S. patent applicationSer. No. 12/936,071 filed on Oct. 1, 2010, which is a U.S. NationalStage Application under 35 U.S.C. §371 of PCT Application No.PCT/KR2009/001679 filed on Apr. 1, 2009, which claims priority to KoreanPatent Application No. 10-2008-0030106 filed on Apr. 1, 2008, whoseentire disclosures are hereby incorporated by reference.

TECHNICAL FIELD

The present invention relates to a light emitting device and a method ofmanufacturing the same.

BACKGROUND ART

Recently, a light emitting diode (LED) is spotlighted as a lightemitting device. Since the LED can convert electric energy into lightenergy with high efficiency and long life span of about 5 years or more,the LED can remarkably reduce the energy consumption and repair andmaintenance cost. In this regard, the LED is spotlighted in thenext-generation lighting field.

Such an LED includes a first conductive semiconductor layer, an activelayer and a second conductive semiconductor layer, in which the activelayer generates light according to current applied thereto through thefirst and second conductive semiconductor layers.

The LED may be classified into a lateral type LED and a vertical typeLED.

According to the lateral type LED, a first conductive semiconductorlayer, an active layer and a second conductive semiconductor layer areformed on a growth substrate, and the second conductive semiconductorlayer, the active layer and the first conductive semiconductor layer arepartially removed such that a part of the first conductive semiconductorlayer can be exposed to form an electrode layer. Thus, the lightemitting area may be reduced so that the light efficiency may bedegraded.

In addition, according to the lateral type LED, since the firstconductive semiconductor layer, the active layer and the secondconductive semiconductor layer are formed on the growth substrate havinglow thermal conductivity, the heat dissipation is not easy.

In contrast, according to the vertical type LED, a first electrode layeris formed on the first conductive semiconductor layer and a secondelectrode layer is formed under the second conductive semiconductorlayer, so it is not necessary to remove the active layer to form theelectrode layer. Thus, the light emitting area may not be reduced, sothat the light efficiency may be improved as compared with that of thelateral type LED.

In addition, according to the vertical type LED, heat is transferredthrough the second electrode layer, so the heat dissipation is easy.

Meanwhile, the vertical type LED may employ the electroplating schemeand the wafer bonding scheme when the second electrode serving as asupport substrate is formed under the second conductive semiconductorlayer.

If the support substrate is manufactured through the electroplatingscheme, the manufacturing process may be facilitated, but thereliability for the LED may be degraded. In addition, if the supportsubstrate is manufactured through the wafer bonding scheme, themanufacturing process may be complicated, but the reliability for theLED may be improved. In particular, if the support substrate ismanufactured through the wafer bonding scheme, since the growthsubstrate and the support substrate are made from heterogeneousmaterials, the crack or debonding may occur in the LED after the waferhas been bonded due to thermal stress caused by difference in thermalexpansion coefficient.

In the vertical type LED, a first electrode layer is formed on the firstconductive semiconductor layer by separating a growth substrate.However, when the growth substrate is separated by using a laser beam,an LED having a light emission area exceeding the area of the laser beamcan not be manufactured.

DISCLOSURE Technical Problem

The embodiment provides a light emitting device having a novel structureand a method of manufacturing the same.

The embodiment provides a method of manufacturing a light emittingdevice by using a novel wafer bonding scheme.

The embodiment provides a light emitting device having a large lightemission area and a method of manufacturing the same.

Technical Solution

According to the embodiment, the light emitting device includes asupport substrate, a reflective ohmic contact layer on the supportsubstrate, a functional complex layer including a process assistingregion and ohmic contact regions divided by the process assisting regionon the reflective ohmic contact layer, and a light emittingsemiconductor layer including a second conductive semiconductor layer,an active layer, and a first conductive semiconductor layer on eachohmic contact region.

According to the embodiment, the light emitting device includes asupport substrate, a reflective ohmic contact layer on the supportsubstrate, a functional complex layer including a process assistingregion and ohmic contact regions surrounded by the process assistingregion on an outer peripheral surface of the reflective ohmic contactlayer, and a light emitting semiconductor layer including a secondconductive semiconductor layer, an active layer, and a first conductivesemiconductor layer on the ohmic contact regions.

According to the embodiment, a method of manufacturing a light emittingdevice includes preparing a first structure including a first conductivesemiconductor layer on a growth substrate, an active layer on the firstconductive semiconductor layer, a second conductive semiconductor layeron the active layer, a functional complex layer including a processassisting region and ohmic contact regions divided by the processassisting region on the second conductive semiconductor layer, and areflective ohmic contact layer on the function complex layer, preparinga second structure on a support substrate, preparing a third structureon a temporary substrate, forming a complex structure by bonding thefirst to third structures through a wafer bonding layer whileinterposing the second structure between the first and third structures,separating the growth substrate from the complex structure, forming alight emitting semiconductor layer having a plurality of unit structuresby selectively etching the first conductive semiconductor layer, theactive layer, and the second conductive semiconductor layer such thatthe process assisting region is exposed, forming a first electrode layeron the first conductive semiconductor layer, and removing the temporarysubstrate.

Advantageous Effects

The embodiment can provide a light emitting device having a novelstructure and a method of manufacturing the same.

The embodiment can provide a method of manufacturing a light emittingdevice by using a novel wafer bonding scheme.

The embodiment can provide a light emitting device having a large lightemission area and a method of manufacturing the same.

DESCRIPTION OF DRAWINGS

FIG. 1 is a sectional view showing the structure of a light emittingdevice according to a first embodiment;

FIGS. 2 to 15 are sectional views showing a method of manufacturing thelight emitting device according to the first embodiment;

FIG. 16 is a view showing the structure of a light emitting deviceaccording to a second embodiment; and

FIGS. 17 to 19 are the method of manufacturing the light emitting deviceaccording to the second embodiment.

MODE FOR INVENTION

In the description of the embodiments, it will be understood that, whena layer (or film), a region, a pattern, or a structure is referred to asbeing “on” or “under” another substrate, another layer (or film),another region, another pad, or another pattern, it can be “directly” or“indirectly” on the other substrate, layer (or film), region, pad, orpattern, or one or more intervening layers may also be present. Such aposition of the layer has been described with reference to the drawings.

The thickness and size of each layer shown in the drawings may beexaggerated, omitted or schematically drawn for the purpose ofconvenience or clarity. In addition, the size of elements does notutterly reflect an actual size.

FIG. 1 is a view showing the structure of a light emitting deviceaccording to a first embodiment.

Referring to FIG. 1, the light emitting device according to the firstembodiment includes a support substrate 210, a diffusion barrier layer70 on the support substrate 210, a reflective ohmic contact layer 60 onthe diffusion barrier layer 70, a functional complex layer 50 on thereflective ohmic contact layer 60, a light emitting semiconductor layerincluding a second conductive semiconductor layer 40, an active layer30, and a first conductive semiconductor layer 20 on the functionalcomplex layer 50, and a first electrode layer 900 on the light emittingsemiconductor layer.

In addition, a die-bonding layer 240 may be formed under the supportsubstrate 210, and may be firmly bonded to a printed circuit board, inwhich the light emitting device is installed, or a die with lowresistance.

The support substrate 210 includes an electric conductive layer. Thesupport substrate 210 may include a wafer substrate including at leastone selected from the group consisting of Si, SiGe, ZnO, GaN, AlSiC, andGaAs. The support substrate 210 may include metal including at least oneselected from the group consisting of Cu, Ni, Ag, Al, Nb, Ta, Ti, Au,Pd, W, and the alloy thereof, or a solid solution.

The support substrate 210 has the form of a sheet, a disk, or a foil ata thickness in the range of 10 μm to 1 mm. The support substrate 210 maybe formed through an electro-plating scheme, a PVD (Physical VaporDeposition) scheme or a CVD (Chemical Vapor Deposition) scheme.

In addition, first and second wafer bonding layers 80 and 230 may beinterposed between the support substrate 210 and the reflective ohmiccontact layer 60. The first and second wafer bonding layers 80 and 230allow the support substrate 210 to be firmly bonded to the reflectiveohmic contact layer 60.

The first and second wafer bonding layers 80 and 230 include an electricconductive layer having strong bonding strength at predeterminedpressure and temperature. For example, the first and second waferbonding layers 80 and 230 may include at least one selected from thegroup consisting of Au, Ag, Al, Si, Ge, W, Mo, V, Sc, Hf, Ir, Re, Co,Zr, Ru, Ta, Nb, Mn, Rh, Cu, Ni, Ti, Pd, Pt, Cr, and rare-earth metal.

In addition, a passivation layer 700 may be formed at a lateral side ofthe light emitting semiconductor layer, and a light extracting structure800 may be formed on the light emitting semiconductor layer.

The diffusion barrier layer 70 prevents a material constituting thefirst and second wafer bonding layers 80 and 230 from being diffusedinto the reflective ohmic contact layer 60 when the first and secondwafer bonding layers 80 and 230 are bonded to each other at atemperature in the range of about 300° C. to about 600° C.

The functional complex layer 50 includes a process assisting region 51,an ohmic contact region 52, and a current blocking region 53.

The ohmic contact region 52 is divided into a plurality of regions bythe process assisting region 51, and the current blocking region 53 isprovided in the ohmic contact region 52.

The process assisting region 51 may have the form of a lattice cell.Light emitting semiconductor layers including the second conductivesemiconductor layer 40, the active layer 30, and the first conductivesemiconductor layer 20 are in regions divided by the process assistingregion 51.

The process assisting region 51 may include an electric insulatingmaterial or a material forming a schottky contact interface with respectto the second conductive semiconductor layer 40. For example, theprocess assisting region 51 may include one selected from the groupconsisting of Al₂O₃, SiN, TiO₂, ZrO₂, Si₃N₄, and SiO₂.

The process assisting region 51 prevents the light emittingsemiconductor layer from being damaged when a growth substrate isseparated through a laser lift off scheme using a laser beam, so thatthe growth substrate can be separated without damage. In addition, theprocess assisting region 51 can prevent the performance of the lightemitting device from being damaged due to etch products created in anisolation etching process to divide the light emitting semiconductorlayer into a plurality of unit structures.

The process assisting region 51 may include a material having superioradhesive property with a material constituting the light emittingsemiconductor layer and having low reactivity with dry etch particlesused in the isolation etching process.

When the passivation layer 700 is formed, the process assisting region51 assists the passivation layer 700 having superior quality to beformed.

The ohmic contact region 52 forms an ohmic contact interface having lowinterfacial contact resistance together with the second conductivesemiconductor layer 40, and allows current to be smoothly applied fromthe outside to the light emitting semiconductor layer perpendicularly tothe light emitting semiconductor layer.

The ohmic contact region 52 may include a transparentor having opticallyhigh transmittance or a reflector having a high reflective rate. Forexample, if the ohmic contact region 52 is the transparentor, the ohmiccontact region 52 may include at least one selected from the groupconsisting of ITO, ZnO, IZO, and NiO—Au. If the ohmic contact region 52is a reflector, the ohmic contact region 52 may include at least oneselected from the group consisting of Ag, alloy containing Ag, solidsolution containing Ag, Rh, alloy containing Rh, solid solutioncontaining Rh, Al, alloy containing Al, and solid solution containingRh.

The current blocking region 53 prevents current applied to the lightemitting semiconductor layer from being concentrated on a portion of thelight emitting semiconductor layer, so that the current can be widelyspread. For example, the current blocking region 53 may include one ofan electric insulating material, empty space filled with air, and amaterial forming a schottky contact interface with respect to the secondconductive semiconductor layer 40.

Although not shown, the current blocking region 53 may be divided into aplurality of regions.

The light emitting semiconductor layer including the second conductivesemiconductor layer 40, the active layer 30, and the first conductivesemiconductor layer 20 may include a nitride-based semiconductormaterial, which is a group III compound semiconductor material. Forexample, the first conductive semiconductor layer 20 may include agallium nitride layer including an N type dopant such as Si, and thesecond conductive semiconductor layer 40 may include a P type dopantsuch as Mg. The active layer 30 emits light through the combination ofelectrons and holes. For example, the active layer may include one ofInGaN, AlGaN, GaN, and AlInGaN. The wavelength of light emitted from theactive layer 30 varies according to the type of a material constitutingthe active layer 30.

Meanwhile, although not shown, an interface modification layer may beadditionally interposed between the second conductive semiconductorlayer 40 and the functional complex layer 50.

The interfacial modification layer may include a supperlatticestructure, one of InGaN, GaN, AlInN, AlN, InN, and AlGaN doped withfirst conductive impurities, one of InGaN, GaN, AlInN, AlN, InN, andAlGaN doped with second conductive impurities, or one of group IIInitride-based elements having a nitrogen-polar surface. In particular,the interfacial modification layer having the supperlattice structuremay include a nitride or a carbon nitride including group II, III, or IVelements.

The light emitting semiconductor layer is formed on the ohmic contactregion 52 divided into a plurality of regions by the process assistingregion 51, and the passivation layer 700 is formed at portions oflateral and top surfaces of the light emitting semiconductor layer.

At least a portion of the passivation layer 700 is provided on theprocess assisting region 51. For example, the passivation layer 700 mayinclude one of SiO₂, Al₂O₃, and Si₃N₄ which are electric insulatingmaterials.

The passivation layer 700 allows the light emitting semiconductor layerto be supported more stably, and prevents electrical short fromoccurring at the light emitting semiconductor layer.

The first electrode layer 900 is formed on the first conductivesemiconductor layer 20, and can commonly make contact with unitstructures of the first conductive semiconductor layer 20. In addition,a portion of the first electrode layer 900 is provided in thepassivation layer 700 and overlaps with the light emitting semiconductorlayer perpendicularly to the light emitting semiconductor layer.

The first electrode layer 900 makes ohmic contact with the firstconductive semiconductor layer 20.

The light extracting structure 800 is formed on the first conductivesemiconductor layer 20 and allows light emitted from the active layer 30to be effectively extracted to the outside. For example, the lightextracting structure 800 may be formed by selectively etching the firstconductive semiconductor layer 20, or may be formed in the patternobtained by selectively etching a nitride layer which is formed on thefirst conductive semiconductor layer 20 and does not include impurities.

FIGS. 2 to 15 are sectional views showing the method of manufacturingthe light emitting device according to the first embodiment.

Referring to FIGS. 2 and 3, the light emitting semiconductor layerincluding the first conductive semiconductor layer 20, the active layer30, and the second conductive semiconductor layer 40 is formed on thesubstrate 10. In addition, the functional complex layer 50 is formed onthe second conductive semiconductor layer 40.

For example, the substrate 10 may include one of Al₂O₃, SiC, silicon Siand gallium arsenide GaAs.

Although not shown, before the first conductive semiconductor 20 isgrown on the growth substrate 10, a buffer layer including at least oneof InGaN, AlN, SiC, SiCN, and GaN may be formed on the growth substrate10.

In addition, the interface modification layer may be formed between thesecond conductive semiconductor layer 40 and the functional complexlayer 50.

The functional complex layer 50 includes the process assisting region51, the ohmic contact region 52, and the current blocking region 53.FIG. 3 shows a plan view of the functional complex layer 50.

The process assisting region 51 may be formed in the form of a latticecell, and the ohmic contact region 52 is divided into a plurality ofunit cell regions H by the process assisting region 51. FIG. 3illustrates a case in which the ohmic contact region 52 is divided intofour unit cell regions H by the process assisting region 51.

The area of the unit cell region H is designed to be smaller than anarea of the laser beam used when the substrate 10 is separated, and thearea of the functional complex layer 50 may be designed to be largerthan an area of a laser beam used when the substrate 10 is separated.

The current blocking region 53 may be formed in each unit cell region H.FIG. 3 illustrates the current blocking region 53 extending radiallyfrom the center of the ohmic contact region 52.

Referring to FIG. 4, the reflective ohmic contact layer 60, thediffusion barrier layer 70, and the first wafer bonding layer 80 areformed on the functional complex layer 50. Therefore, a first structure100 shown in FIG. 4 can be manufactured.

Referring to FIG. 5, a second structure 200 including the supportsubstrate 210 provided at a top surface thereof with the second waferbonding layer 230 and provided at a bottom surface thereof with thethird wafer bonding layer 220. The third wafer bonding layer 220 mayinclude the same material as that of the second wafer bonding layer 230.

Referring to FIG. 6, a third structure 300 having a sacrificialseparation layer 320 and a fourth wafer bonding layer 330 is prepared ona temporary substrate 310.

The temporary substrate 310 may include a material making thermalexpansion coefficient difference of 2 ppm/° C. or less from the growthsubstrate 10, or a material the same as that of the growth substrate 10.For example, the temporary substrate 310 may include one of Al₂O₃, SiC,Si, and GaAs.

The sacrificial separation layer 320 may include one of a group II-Vicompound including ZnO, a group III-V compound including GaN, ITO, PZT,and SU-8, which are subject to thermo-chemical decomposition reaction asa laser beam is irradiated thereto, or one of Al, Au, Ag, Cr, Ti, SiO₂,and SiN_(x) which are rapidly dissolved in a wet solution.

The fourth wafer bonding layer 330 may include the same material as thatof the second wafer bonding layer 230.

Referring to FIG. 7, the first structure 100 shown in FIG. 4, the secondstructure 200 shown in FIG. 5, and the third structure 300 shown in FIG.6 are bonded to each other, thereby forming a complex structure.

The first wafer bonding layer 80 is bonded to the second wafer bondinglayer 230, and the third wafer bonding layer 220 is bonded to the fourthwafer bonding layer 330.

The first structure 100, the second structure 200, and the thirdstructure 300 are bonded to each other at a predetermined pressure and apredetermined temperature in the range of about 300° C. to 600° C.

The third structure 300 is positioned corresponding to the firststructure 100 while interposing the second structure 200 between thethird structure 300 and the first structure 100, and the first structure100 has a thermal expansion coefficient similar to that of the thirdstructure 300. Accordingly, the cracks and debonding do not occur due tothe difference in the thermal expansion coefficient when the first andsecond structures 100 and 200 are coupled with each other.

Referring to FIG. 8, the growth substrate 10 is separated from thecomplex structure shown in FIG. 7.

The growth substrate 10 may be separated by using an LLO scheme based onan eximer laser beam, or by using a dry etch scheme or a wet etchscheme.

When the eximer laser beam having a predetermined wavelength is focusedon the growth substrate 10 and irradiated to the growth substrate 10,thermal energy is concentrated on the boundary surface between thesubstrate 10 and the first conductive semiconductor layer 20, so thatthe interfacial surface of the first conductive semiconductor layer 20is thermo-chemically decomposed into into Ga and N. Accordingly, thegrowth substrate 10 is separated.

The used laser beam must have a size greater than a size L2 of the ohmiccontact region 52 divided by the process assisting region 51.

Therefore, if the second laser beam is irradiated after the first laserbeam has been irradiated, the second laser beam overlaps with the firstlaser beam on the process assisting region 51.

Referring to FIG. 9, regions L, M, and N of the light emittingsemiconductor layer on the process assisting region 51 are damaged dueto the overlap of the laser beams.

Referring to FIG. 10, the regions L, M, and N of the light emittingsemiconductor layer on the process assisting region 51 are removedthrough a MESA etching process based on a wet etching process or a dryetching process. Accordingly, the process assisting region 51 isexposed, so that the light emitting semiconductor layer is divided intoa plurality unit structures.

Referring to FIG. 11, the passivation layer 700 is formed on the top andlateral surfaces of the light emitting semiconductor layer. Thepassivation layer 700 may make contact with the process assisting region51.

The passivation layer 700 may have a thickness in the range of about 200nm to about 1000 nm.

Referring to FIG. 12, the passivation layer 700 formed on the lightemitting semiconductor layer is partially removed, and the lightextracting structure 800 is formed on the first conductive semiconductorlayer 20.

The light extracting structure 800 may be formed in an irregularconcave-convex pattern through a wet etching process, or may be formedin a regular concave-convex pattern through a lithography process.

Referring to FIG. 13, the first electrode layer 900 is formed on thefirst conductive semiconductor layer 20.

The first electrode layer 900 can be electrically connected to the unitstructures of the first conductive semiconductor layer 20,simultaneously.

At least a portion of the first electrode layer 900 overlaps with theprocess assisting region 51 perpendicularly to the process assistingregion 51. A portion of the first electrode layer 900 may be filled inthe passivation layer 700.

Referring to FIG. 14, the temporary substrate 310 is exposed throughisolation etching 1000, and a plurality of light emitting devices areformed on the temporary substrate 310.

Referring to FIG. 15, the temporary substrate 310 is removed through anLLO scheme, a dry etching scheme, a wet etching scheme, a CMP scheme, ora polishing scheme.

When the temporary substrate 310 is separated through the LLO scheme,the sacrificial separation layer 320 is thermo-chemically decomposed, sothat the temporary substrate 310 is removed.

After removing the third wafer bonding layer 220 and the fourth waferbonding layer 330, the die-bonding layer 240 is formed under the supportsubstrate 210.

Accordingly, the light emitting device according to the first embodimentcan be manufactured.

FIG. 16 is a sectional view showing a light emitting device according toa second embodiment.

Hereinafter, the light emitting device according to the secondembodiment will be described while focusing on the difference from thelight emitting device according to the first embodiment in order toavoid redundancy.

Referring to FIG. 16, the light emitting device according to the secondembodiment includes the support substrate 210, the diffusion barrierlayer 70 on the support substrate 210, the reflective ohmic contactlayer 60 on the diffusion barrier layer 70, the functional complex layer50 on the reflective ohmic contact layer 60, the light emittingsemiconductor layer including the second conductive semiconductor layer40, the active layer 30, and the first conductive semiconductor layer 20on the functional complex layer 50, and the first electrode layer 900 onthe light emitting semiconductor layer.

The die-bonding layer 240 may be formed under the support substrate 210.

The first and second wafer bonding layers 80 and 230 may be formedbetween the support substrate 210 and the reflective ohmic contact layer60.

The passivation layer 700 may be formed on the lateral surface of thelight emitting semiconductor layer, and the light extracting structure800 may be formed on the light emitting semiconductor layer.

The functional complex layer 50 includes the process assisting region51, the ohmic contact region 52, and the current blocking region 53.

The process assisting region 51 is formed in the vicinity of thereflective ohmic contact layer 60, the ohmic contact region 52 issurrounded by the process assisting region 51, and the current blockingregion 53 is provided in the ohmic contact region 52.

Although not shown, the interface modification layer may be additionallyformed between the second conductive semiconductor layer 40 and thefunctional complex layer 50.

The first electrode layer 900 is formed on the first conductivesemiconductor layer 20. The first electrode layer 900 makes ohmiccontact with the first conductive semiconductor layer 20.

The light extracting structure 800 is formed on the first conductivesemiconductor layer 20, and allows the light emitted from the activelayer 30 to be effectively extracted to the outside.

FIGS. 17 to 19 are sectional views showing the method of manufacturingthe light emitting device according to the second embodiment.

In the method of manufacturing the light emitting device according tothe second embodiment, most of process steps are similar to those of themethod of manufacturing the light emitting device according to the firstembodiment. In particular, the method of manufacturing the lightemitting device according to the first embodiment described withreference to FIGS. 2 to 12 is identical to the method of manufacturingthe light emitting device according to the second embodiment.

Accordingly, the method of manufacturing the light emitting deviceaccording to the second embodiment corresponding to the manufacturingmethod that has been described with reference to FIGS. 2 to 12 will beomitted in order to avoid redundancy.

Referring to FIG. 17, the first electrode layer 900 is formed on eachunit structure of the first conductive semiconductor layer 20 shown inFIG. 12.

Referring to FIG. 18, after performing the isolation etching 1000 toexpose the temporary substrate 310, a plurality of light emittingdevices are formed on the temporary substrate 310.

Referring to FIG. 19, the temporary substrate 310 is removed through theLLO scheme, the dry etching scheme, the wet etching scheme, the CMPscheme, or the polishing scheme.

When the temporary substrate 310 is separated through the LLO scheme,the sacrificial separation layer 320 is thermo-chemically decomposed, sothat the temporary substrate 310 is removed.

After removing the third and fourth wafer bonding layers 220 and 330,the die-bonding layer 240 is formed under the support substrate 210.

Accordingly, the light emitting device according to the secondembodiment can be manufactured.

Although embodiments have been described with reference to a number ofillustrative embodiments thereof, it should be understood that numerousother modifications and embodiments can be devised by those skilled inthe art that will fall within the spirit and scope of the principles ofthis disclosure. More particularly, various variations and modificationsare possible in the component parts and/or arrangements of the subjectcombination arrangement within the scope of the disclosure, the drawingsand the appended claims. In addition to variations and modifications inthe component parts and/or arrangements, alternative uses will also beapparent to those skilled in the art.

INDUSTRIAL APPLICABILITY

The embodiment is applicable to the method of manufacturing thesemiconductor device used as an electronic device or a light source.

What is claimed is:
 1. A light emitting device comprising: a supportsubstrate; a reflective layer on the support substrate; a first layerincluding ohmic contact regions on the reflective layer; a lightemitting semiconductor layer disposed on the first layer and including asecond conductive semiconductor layer, an active layer on the secondconductive semiconductor layer, and a first conductive semiconductorlayer on the active layer; and a top surface of the first conductivesemiconductor layer has a flat surface, a light extracting structure onthe flat surface.
 2. The light emitting device of claim 1, furthercomprising a diffusion barrier layer between the support substrate andthe reflective layer.
 3. The light emitting device of claim 2, furthercomprising a wafer bonding layer between the diffusion barrier layer andthe support substrate.
 4. The light emitting device of claim 1, whereinthe wafer bonding layer including a first wafer bonding layers and asecond wafer bonding layers.
 5. The light emitting device of claim 1,wherein the top surface of the first conductive semiconductor layer anda bottom surface of the first conductive semiconductor layer aresubstantially parallel each other.
 6. The light emitting device of claim1, wherein the light extracting structure contacts the top surface ofthe first conductive semiconductor layer.
 7. The light emitting deviceof claim 1, further comprising a first electrode disposed on the lightemitting semiconductor layer.
 8. The light emitting device of claim 7,wherein a lowermost surface of the first electrode is lower than a topsurface of the active layer.
 9. The light emitting device of claim 7,wherein a top surface of the first electrode is higher than a topsurface of the light extracting structure.
 10. The light emitting deviceof claim 1, further comprising a die-bonding layer is disposed under thesupport substrate.
 11. The light emitting device of claim 1, wherein thelight extracting structure is formed in the pattern obtained byselectively etching a nitride layer which is formed on the firstconductive semiconductor layer and does not include impurities.
 12. Thelight emitting device of claim 1, wherein the first layer including aprocess assisting region, and a current blocking region.
 13. The lightemitting device of claim 12, wherein the ohmic contact region is dividedinto a plurality of unit cell regions by the process assisting region.14. The light emitting device of claim 13, wherein the current blockingregion extending radially from the center of the ohmic contact region.15. The light emitting device of claim 1, wherein the ohmic contactregion including at least one selected from the group consisting of ITO,ZnO, IZO, and NiO—Au.
 16. A light emitting device comprising: areflective layer; a light emitting semiconductor layer on the reflectivelayer and including a first top region and a second top region, thefirst and second top regions being substantially flat; a first electrodeon the first top region of the light emitting semiconductor layer; and atop surface of the light emitting semiconductor layer and a bottomsurface of the light emitting semiconductor layer are substantiallyparallel each other; a light extracting structure on the second topregion of the light emitting semiconductor layer.
 17. The light emittingdevice of claim 16, further comprising a complex layer on the reflectivelayer.
 18. The light emitting device of claim 17, wherein the functionalcomplex layer including a process assisting region, a ohmic contactregion, and a current blocking region.
 19. The light emitting device ofclaim 18, wherein the ohmic contact region is divided into a pluralityof unit cell regions by the process assisting region.
 20. The lightemitting device of claim 19, wherein the current blocking regionextending radially from the center of the ohmic contact region.